Baczartan Mechanism of Action

Angiotensin II Receptor Blocker.
Pharmacology: Pharmacodynamics: Losartan is orally active, non-peptide angiotensin II receptor antagonist. Losartan and its active metabolite block the vasoconstrictor and aldosterone-secreting effects of angiotensin II selectively blocking the binding of angiotensin II to the AT, receptor found in many tissues (e.g., vascular smooth muscle, adrenal gland).
Pharmacokinetics: Losartan is readily absorbed from the gastrointestinal tract following oral administration with an oral bioavailability of about 33%. It undergoes first-pass metabolism to form an active carboxylic acid metabolite E-3174, which has greater pharmacological activity than Losartan and some inactive metabolites. Peak plasma concentrations of Losartan and E-3174 occur about 1 hour and 3 to 4 hours, respectively, after an oral dose. Both Losartan and E-3174 are more than 98% bound to plasma proteins. Losartan is excreted in the urine and in feces via bile, as an unchanged drug and metabolites. Following oral dosing about 35% of the dose is excreted in the urine and about 60% in the feces. The terminal elimination half-lives of Losartan and E-3174 are about 1.5 to 2.5 hours and 3 to 9 hours respectively.